Ella Advocacy Deborah lived near the South Circular Road, which is one of London's busiest routes.

In the three years before her death, she suffered multiple seizures on was admitted to hospital on 27 occasions.

Today in a landmark ruling, a second inquest into her death found that air pollution made a material contribution to her death.

Our environment correspondent Clare Marshall has the story.

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A was a healthy child before suddenly starting to suffer asthma attacks so severe she ended up on a ventilator.

This'll cough an early sign of some of the damage being done to her lungs.

We now know without doubt, by air pollution if you Deborah who you will know today's decision was the result her mother has been campaigning for for years.

We've got the justice for her, which is so deserved, but also it's about other Children.

Still, as we walk around our city off high levels of air pollution, Ellis Family Home was beside London's busy South circular road, she would walk to school along it.

At the time, no connection was made between Ellis fatal asthma attack and air pollution.

Their new medical evidence emerged.

I wanted the real reason why she went through what she went through.

I hope through this her legacy, Uh, maybe a new clean air act.

I think the only bit I got a little bit angry was in court when it turned out that lots of people knew about it.

And yet the response has been so slow.

The original inquests was quashed, and today the coroner ruled that levels of toxic gasses and pollutants and exhausts were way above safe levels set by the World Health Organization.

Without doubt, they contributed to her death.

She was drowning in her secretions each time she had one of these dreadful attacks on the fact that they clustered together on that These were in the winter on daughter months, when the air pollution was worse in London, putting all that together, it suddenly started to make sense.

This isn't just about London.

This is about the whole of the UK.

One expert witness said that the Children breathing in these fumes should be treated as seriously as if they're breathing in secondhand smoke.

Perhaps parents should be advised to take a different route to school.

The experts are now calling for lessons to be learned from Ella's death.

It will mean that we can protect Children's health.

Going forward on what we do need to do is develop the education and the tools needed to talk about air pollution.

And hopefully the government will take air pollution reduction as a national priority.

She she would be very proud that her name is being used to do something really positive because I've always said to you she was incredibly kind, So this is the sort of thing she would approve off.

The government says it's spending almost £4 billion on tackling air pollution in its setting new, ambitious targets.

But this is no longer about anonymous statistics.

It's about the life, terrible suffering and death of a child who was breathing poisonous air.